U.S. patent number 4,928,300 [Application Number 07/339,805] was granted by the patent office on 1990-05-22 for videophone with detachable tv camera.
This patent grant is currently assigned to Mitsubishi Denki Kabushiki Kaisha. Invention is credited to Kohji Ogawa, Mikio Onoki.
United States Patent |
4,928,300 |
Ogawa , et al. |
May 22, 1990 |
Videophone with detachable TV camera
Abstract
A videophone is provided wherein a TV camera is detachable from
the videophone unit for the purpose of facilitating the operation
of the TV camera when imaging subjects other than the user.
Inventors: |
Ogawa; Kohji (Gunma,
JP), Onoki; Mikio (Gunma, JP) |
Assignee: |
Mitsubishi Denki Kabushiki
Kaisha (Tokyo, JP)
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Family
ID: |
26485725 |
Appl.
No.: |
07/339,805 |
Filed: |
April 18, 1989 |
Foreign Application Priority Data
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Jun 27, 1988 [JP] |
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63-158688 |
Jul 29, 1988 [JP] |
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63-189908 |
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Current U.S.
Class: |
348/14.01;
348/E7.079 |
Current CPC
Class: |
H04N
7/142 (20130101) |
Current International
Class: |
H04N
7/14 (20060101); H04M 011/00 (); H04N 007/14 () |
Field of
Search: |
;379/53,54
;358/85,224,229 |
References Cited
[Referenced By]
U.S. Patent Documents
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4291198 |
September 1981 |
Anderson et al. |
4485400 |
November 1984 |
Lemelson et al. |
4715059 |
December 1987 |
Cooper-Hart et al. |
4739413 |
April 1988 |
Meyer |
|
Foreign Patent Documents
Primary Examiner: Ng; Jin F.
Assistant Examiner: Chan; Wing F.
Attorney, Agent or Firm: Wolf, Greenfield & Sacks
Claims
What is claimed is:
1. A videophone comprising:
a TV camera detachably accommodated in the unit of said videophone,
said TV camera being connected to the videophone unit through a
cable;
means for displaying image data picked-up by said TV camera or
image data transmitted through a telephone line; and
means for detecting whether or not said TV camera is fixed in the
videophone unit;
the image displayed on said displaying means being automatically
switched between a reflected image and a true image in response to
the output from said detecting means.
2. A videophone comprising:
a TV camera connected via a signal cable to a videophone unit and
detachably accommodated in said videophone;
a detecting means for detecting whether or not said TV camera is
accommodated in said videophone unit;
an image display means for displaying image data generated by said
TV camera or image data transmitted through a telephone line;
an image memory for storing said image data; and
an image processing means for processing said image data generated
by said TV camera to be displayed as a reflected image on said
image display means and for storing in said image memory the image
data with a flag indicative of the fact that said TV camera is
fixed within said videophone when receiving a detecting signal
indicative of the fact that said TV camera is accommodated with
said videophone from said detecting means, said image processing
means displaying said image data as a reflected image on said image
display means when said image data read out from said image memory
is flagged, and said image processing means displaying said image
data on said image display means as true images when both said
image data is generated by said TV camera when detached from said
videophone and said image data is transmitted through said
telephone line.
3. A videophone comprising, a videophone unit having an image
display means, a TV camera, said videophone unit having means for
detachably receiving said TV camera, said TV camera having a cable
for coupling to said videophone unit, said TV camera adapted to be
either in a received position at said videophone unit or detached
therefrom, control means for displaying image date on said image
display means either picked up by said TV camera or received from a
telephone line, means for detecting whether or not said TV camera
is in the received position, wherein said means for detecting
includes light path detection means.
4. A videophone comprising, a videophone unit having an image
display means, a TV camera, said videophone unit having means for
detachably receiving said TV camera, said TV camera having a cable
for coupling to said videophone unit, said TV camera adapted to be
either in a received position at said videophone unit or detached
therefrom, control means for displaying image date on said image
display means either picked up by said TV camera or received from a
telephone line, means for detecting whether or not said TV camera
is in the received position, wherein said control means for
displaying image data is controlled to switch between true and
reflected images in response to the output from said detecting
means.
5. A videophone as set forth in claim 4 wherein the control means
displays a reflected image when the camera is in its received
position and displays a true image when the camera is in its
detached position.
6. A videophone as set forth in claim 4 wherein the control means
includes an image memory and image processing means.
7. A videophone as set forth in claim 6 wherein the image
processing means is for processing said image data generated by
said TV camera to be displayed as a reflected image on said image
display means and for storing in said image memory, the image data
with a flag indicative of the fact that the TV camera is in its
received position.
8. A videophone as set forth in claim 7 wherein the image
processing means displays the image data as a reflected image on
the image display means when the image data read out from the image
memory is flagged.
9. A videophone as set forth in claim 8 wherein the image
processing means displays the image data on the image display means
as true images when both the image data is generated by the TV
camera when detached from the videophone unit and the image data is
transmitted through the telephone line.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to a videophone and, more
particularly, to a videophone with a TV camera detachable in such a
manner that the operation of the videophone is greatly
facilitated.
2. Prior Art
A typical conventional videophone is shown in the perspective view
of FIG. 1 in which a TV camera 2 is incorporated in a videophone
unit 1, the photosensitive surface of TV camera 2 being disposed on
a front surface 3. The videophone unit 1 is provided with a CRT
display 4 which functions as an image display means for displaying
image data picked-up by a user's own TV camera 2 or image data
transmitted from the videophone of another party during video
telephone communication via a telephone line. The display surface
of the CRT display 4 is disposed on a front surface 3. Variety
operation buttons 5 are also provided on the front surface 3.
FIG. 2 is a block diagram depicting the internal constitution of a
videophone. In FIG. 2, an image control unit 11 controls the image
data picked-up by TV camera 2 and the image data read from an image
memory 12. The thus controlled image data are supplied and
displayed on CRT display 4. Subsequently, the image data are also
delivered to image memory 12 and stored therein.
A group of multiple switches 13 is turned ON/OFF by various
operation buttons 5 (FIG. 1). Based on switching signals from
switch group 13, a microcomputer 14 functions to take the image
data out of image control unit 11 to an image transmission unit 15,
and vice versa.
A line interface 16 selectively connects image transmission unit 15
and a telephone 17 to a telephone line 18. The numeral 19
represents a power supply for the videophone unit. It is noted that
the image control unit 11 and microcomputer 14 are combined to
constitute an image processing unit 20.
The description will next deal with the operation of the
videophone. The data of the user's own image formed by TV camera 2
is taken into image control unit 11 and undergoes an inversion
process in accordance with a command issued from microcomputer 14
on the basis of the switch signals transmitted from switch group
13. Subsequent to this step, the image data is displayed as a
reflected image on CRT display 4.
More specifically, the user's face which faces the videophone 1 is
imaged as a true image (the user's face as viewed by the other
party) by means of TV camera 2. If the true image were to be
displayed directly on the CRT display 4, however, the user who is
accustomed to looking at his own image in a mirror may feel it to
be quite unnatural. It is thus required that the image be displayed
as a reflected image on the CRT display 4. Consequently the
abovementioned inversion display is effected.
The image data obtained when imaging a subject other than the user
himself by use of TV camera 2 is displayed as a true image directly
on CRT display 4 without effecting inversion. Similarly displayed
on CRT display 4 is the image data transmitted from the other party
in the ongoing video telephone communication to the image control
unit 11 via the telephone line, line interface 16, image
transmission unit 15 and microcomputer 14.
On the other hand, when transmitting the image data of the user's
image formed by TV camera 2 to the other party, the image data from
TV camera 2 is temporarily stored in image memory 12 through image
control unit 11.
Subsequently, the image data read from image memory 12 is
transmitted to the other party via microcomputer 14, image
transmission unit 15, line interface 16 and telephone line 18. The
image data is then displayed as a true image on the CRT display 4
of the other party.
The thus constructed prior art videophone system is attended by the
following problems. If, in addition to the user's face, another
subject, e.g., a child who is playing nearby is to be shown, the
videophone unit itself has to be moved to direct the TV camera
toward the freely moving target subject, because the TV camera is
integrally incorporated therein. It is thus rather difficult to
direct the TV camera to a target subject.
Accordingly, it is a primary object of the present invention to
obviate the foregoing problems and to provide a novel videophone
capable of readily directing a TV camera toward a target subject
for bringing into focus that target without moving the whole
videophone unit, and which is also capable of displaying the user's
image as a reflected image while displaying images other than the
user's image as true images.
SUMMARY OF THE INVENTION
A videophone according to the present invention is arranged in such
a manner that a TV camera is constructed separately from a
telephone unit but detachably mounted therein.
The videophone according to the invention includes a detecting
means for detecting the state of the TV camera, that is whether or
not the TV camera is detached, the detecting means generating a
detection signal by means of which an image displayed on a CRT
display on the transmitting side is automatically changed to a
reflected image or a true image.
A videophone incorporating a further feature of the invention
comprises: a TV camera detachably mounted on a telephone unit; a
detecting means for detecting whether the TV camera is mounted
thereon or demounted therefrom; an image display means; an image
memory; and an image processing means for permitting image data
formed by the TV camera to be displayed as a reflected image on the
image display means by inverting the image data, storing in the
image memory a flag indicative of a condition under which the TV
camera is fixed, the flag being set in the image data, and
displaying as a reflected image the image data read from the image
memory on the image display means when a detection signal from the
detecting means indicates that the TV camera is accommodated in the
telephone unit, and displaying the image data formed by the TV
camera and the image data transmitted through a telephone line as
true images on the image display means when the detection signal
indicates that the TV camera is demounted.
With such an arrangement, the TV camera can be demounted from the
telephone unit, and hence a subject other than the user can be
imaged with ease. When employing the TV camera in the demounted
condition, the appearance of a subject as viewed by the user is
displayed as a true image directly on a CRT display in accordance
with a detection signal indicating whether the TV camera is mounted
or demounted relative to the telephone unit. When the TV camera is
mounted thereon, i.e., when imaging the user's face, a reflected
image obtained after inversion is displayed on the CRT display.
When the image data formed by the TV camera is stored in the image
memory, the image data is stored while setting therein a flag
indicative of the condition of the TV camera with respect to the
telephone unit. The image based on this image data is selectively
displayed as a reflected image or a true image depending on whether
the image data read from the image memory is flagged or not.
The invention, as well as other objects and advantages thereof,
will become more apparent from the following detailed description
of a preferred embodiment in connection with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the invention, reference is made to
the accompanying drawings, in which:
FIG. 1 is a perspective view of a videophone in the prior art;
FIG. 2 is a block diagram illustrating the constitution of the
videophone shown in FIG. 1;
FIG. 3 is a perspective view of a videophone in accordance with the
present invention;
FIG. 3A is a block diagram illustrating the constitution of the
videophone shown in FIG. 3;
FIG. 4 is a table showing image data as a comparison between the
cases where a TV camera is fixed to a videophone unit and detached
therefrom with respect to image data from the TV camera, the state
of display on a user's own CRT display, image data transmitted to
the other party in video telephone communication with the user, and
image data sent from the other party;
FIG. 5 is a flowchart showing an operation for storing in a memory
the image data picked-up by the TV camera;
FIG. 6 shows a pattern in an image register; and
FIG. 7 is a flowchart showing an operation for reading out the
image data stored in the memory.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 3, there is shown the perspective view of a
videophone unit in accordance with the present invention. In FIG.
3, the same reference numerals are used for components which
correspond to those shown in FIG. 1.
In FIG. 3, a TV camera 6 is detachable from a videophone unit 1. TV
camera 6 may be accommodated in a camera accommodation section 7,
the opening of which is formed in a front surface of unit 1. The TV
camera is connected through a stretchable signal cable 8 to unit 1,
the cable having a spiral configuration and transmitting the image
data formed by TV camera 6 to an image control unit incorporated in
videophone unit 1.
Attached to an inner wall of the camera accommodation section 7 is
a detecting means 9 for detecting whether or not TV camera 6 is
installed therein. The detecting means 9 in this embodiment is
composed of a light receiving element 9a and a light emitting
element (not illustrated) which are disposed in face-to-face
fashion. The presence or absence of TV camera 6 in section 7 is
detected by checking whether or not the light emitted from the
light emitting element to the light detecting element is blocked by
TV camera 6.
Next, the operation of the embodiment will be explained as follows.
The internal configuration of videophone unit 1 is similar to that
in the prior art, and the operation will be described in
conjunction with FIG. 3A.
When the user's face is imaged for display and transmission
thereof, TV camera 6 is typically used with the camera set in
camera accommodation unit 7 of videophone 1. When TV camera 6 is
accommodated in camera accommodation unit 7, a detecting means 9
behaves to detect the presence of the TV camera from the fact that
the light travelling to the light detecting element has been
intercepted. Then, the detecting means supplies microcomputer 14
with a command that the image data should be inverted (to a
reflected image).
An image control unit 11 inverts the image data of a user's image
generated by TV camera 6 in accordance with the instruction given
by microcomputer 14 indicating that the image data should be
inverted, and the thus-processed image data is displayed as a
reflected image on CRT display 4.
In the case of demounting TV camera 6 from videophone 1 in order to
image a subject other than the user himself, detecting means 9
detects the absence of TV camera 6 from the fact that the light
emerging from the light emitting element reaches light detecting
element 9a and gives microcomputer 14 an instruction to the effect
that the inversion of the image data is not necessary.
Thus, in accordance with the instruction from microcomputer 14, the
image control unit 11 permits the display of the image data imaged
by TV camera 6 on CRT display 4 as a true image identical with the
subject's image as observed by the user, unlike the case where the
user's face is imaged.
On the other hand, when the image data generated by TV camera 6 is
transmitted to the other party in video telephone communication
with him through microcomputer 14, an image transmission unit 15, a
line interface 16 and a telephone line 18, the image data is
transmitted without being inverted irrespective of whether the
subject involves the user's face or something also. Thus, the image
data is displayed as a true image on the CRT display of the other
party.
FIG. 4 is a table showing a comparison between the case where TV
camera 6 is inserted into videophone unit 1 and the case where it
is detached therefrom with respect to the output image data
supplied from TV camera 6, the display of the user's image on the
user's own CRT display, the image data to be transmitted to the
other party and the image data sent from the other party. As is
obvious from this table, only the image data of the user's face
imaged in the state where TV camera 6 is accommodated in videophone
unit 1 is displayed as a reflected image after inversion.
FIG. 5 is a flowchart showing the operation that takes place when
the image data formed by TV camera 6 is stored in image memory
12.
Referring to FIG. 5, when the videophone is used for monitoring
moving pictures (step ST1), it is determined whether or not TV
camera 6 is fixed (inserted) in videophone unit 1 (step ST2). If
fixed, a moving picture flag is set in a moving picture flag region
10a of an image register 10 depicted in FIG. 6 (step ST3). Thus,
the image data displayed on CRT display 4 is arranged to be a
reflected image with right and left sides reversed (step ST4).
When TV camera 6 is detached from videophone unit 1, the moving
picture flag is not set therein (step ST7). The image data
displayed on the CRT display becomes a normal "true" image (step
ST8).
When TV camera 6 is fixed in videophone unit 1, the image data
generated is stored as the normal image (not the reflected image)
in image memory 12 after a flag has been set in a marking region
10b of image register 10 (steps ST5, ST6 and ST11).
When TV camera 6 is detached from unit 1, the image data generated
is stored as the normal image in image memory 12 without any flag
being set in marking region 10b (steps ST9, ST10 and ST11).
Now, the operation of reading out the stored image data will be
described. Referring to FIG. 7, the operation starts with turning
on a readout switch (not shown) (steps ST12 and ST13). Upon
receiving a readout switch signal, microcomputer 14 confirms
whether or not the flag is set in marking region 10b of image
register 10. If flagged (step ST14), the image data is temporarily
read out from image memory 12 and is rewritten as a reflected image
after inversion in a free region within image memory 12. Then, the
reflected image is read out therefrom and displayed on CRT display
4 (step ST15).
If marking region 10b is not flagged, the image data is read out
from image memory 12 and displayed as a true image directly on CRT
display 4 (step ST16).
It is to be noted that, although in the aforementioned embodiment
detecting means 9 consists of light emitting and detecting element,
it may involve use of a contact type micro-switch or the like.
As discussed above, the present invention provides the following
effects. Since the TV camera is detachably mounted on the visual
telephone body and the state of the TV camera is automatically
detected, the entire videophone need not be moved for imaging
subjects other than the user. This arrangement enables the TV
camera to be directed toward other subjects with ease. Besides
this, the image data of the user's image generated by the TV camera
while it is accommodated in the videophone is displayed as a
reflected image. On the other hand, the image data generated by the
TV camera while it is separated from the telephone body and the
image data transmitted from the other party in video telephone
communication with the user are displayed as "true" images so that
a natural display can be obtained.
* * * * *